A layer to be added to a Leaflet map. It works as a regular tiled layer within the Leaflet tile pane, but instead of containing `<img>` elements, it's composed of a single [`<canvas>`](https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API) where all markers are drawn.
cartocss | A string object, the CartoCSS style for the map. Default value is ```null```
loop | A boolean object that defines the animation loop. Default value is ```true```. If ```false```, the animation is paused when it reaches the last frame
user | A string object, your CartoDB [account name](/cartodb-editor/your-account/#account). Default value is ```null```
table | A string object, the CartoDB table name where data is found (also known as a dataset.) Default value is ```null```
##### Using a custom SQL query
Name | Description
--- | ---
query | A string object, the SQL query to be performed to fetch the data. Default value is ```null```.<br/><br/>You must use this param or table, but not at the same time
**Tip:** For a Torque category layer that is created dynamically with `cartodb.createLayer`, the SQL query must explicitly include how to build the torque_category column. You must include both the `sql` and `table_name` parameters. See this [createLayer with torque category layer](https://gist.github.com/danicarrion/dcaf6f00a71aa55134b4) example.
**Note:** Torque.js interprets the beginning and ending date/time from your "Time Column" as one block, then divides that up into [Steps](/cartodb-platform/cartocss/properties-for-torque/#torque-frame-count-number), depending on the number you set. It does not necessarily draw one frame for each row.
`setCartoCSS(cartocss)` | `cartocss string` | `this` | style the map rendering using client-side CartoCSS (not available with [Named maps](/cartodb-platform/maps-api/named-maps/))
Torque supports a limited subset of CartoCSS rules defined in the [torque-reference](https://github.com/cartodb/torque-reference). To see the full list of supported rules, read the [Torque CartoCSS documentation](/cartodb-platform/cartocss/properties-for-torque/). `value` and `zoom` variables can be used. `value` is the value of aggregation. `zoom` is the current zoom being rendered.
torqueLayer.setSQL("SELECT * FROM table LIMIT 100");
```
### Events
_**Note:** You can only run events after the [required libraries](/cartodb-platform/torque/torquejs-getting-started/#advanced-torquejs-libraries) are loaded. Otherwise, the [interaction methods](/cartodb-platform/torque/torque-interaction-methods/) will not work._
`change:steps` | current step | When a map changes steps, this event is triggered
`change:time` | current time, step number | When a map changes time, this event is triggered
`play` | none | Triggered when the Torque layer is played
`pause` | none | Triggered when the Torque layer is paused
`stop` | none | Triggered when the Torque layer is stopped
`load` | none | Triggered when the Torque layer is loaded
#### Example
An event example to print the current step to the console log.
```js
torqueLayer.on('change:steps', function(step) {
// do something with step
console.log('Current step is ' + step);
});
```
## Google Maps Layers
### GMapsTorqueLayer(_options_)
This class does exactly the same as ``L.TorqueLayer`` but using Google Maps instead. The main difference is that this class
is not a layer but is an overlay, so in order to add it to the a map use, ``layer.setMap`` instead of ``overlayMapTypes``. See the [Overlay View](https://developers.google.com/maps/documentation/javascript/reference#OverlayView) reference in Google Maps API doc.
